Device with a mark-holder hopper and a revolver hopper for stamping distinguishing marks on moving parts

ABSTRACT

The invention relates to a device for stamping distinguishing marks on the parts moving in the feed direction of a transport device, e.g. a roll line, comprising at least one mark-holder for holding a mark, the mark-holder being removably placed on the circumference of a stamping wheel. The inventive device comprises at least one hopper for the mark-holders. The hopper for the mark-holders and the stamping wheel can be placed relatively to one another, in a position where the mark-holders of the stamping wheel can pass through cavities of the mark-holder hopper, and the mark-holders of the mark-holder hopper can pass directly through cavities of the stamping wheel. A revolver hopper comprising mark-holder pins which can move axially with it is rotatably mounted and has the same axis as the stamping wheel. The stamping wheel is provided with at least one outward push channel which extends radially towards the circumference of the stamping wheel, as well as with a linear driving mechanism which is rotationally fixed on the stamping wheel, to allow radial displacement of a mark-holder pin located in an angular position of the outward push channel, between an inner rest position and an outer stamping position.

The present invention relates to a device for the marking of partsmoving in the direction of motion of a conveying device such as a rollertable having at least one character carrier carrying one character, saidcharacter carrier being exchangeably inserted at the circumference of astamping wheel.

Devices for the marking of parts (DD-PS 27177) are known where thestamping characters of a stamping character set are arranged in anexchangeable cartridge, said exchangeable cartridge being removablyinserted into the stamping wheel so that exchanging of the stampingcharacter set only requires insertion of a new cartridge containing theprepared stamping character set. Exchanging of individual stampingcharacters within one character set, however, is not possible in thiscase. Additionally, such devices are not able to meet the ever greaterrequirements in terms of production speed and automation.

Devices for the exchanging of individual character carriers are alsoknown (AT 398 916). In this type of device, the stamping wheel forms aring-shaped guide, coaxial with the rotational axis, for the charactercarriers. The stamping character storage can be rotated stepwise, inrelation to the stamping wheel, around the rotational axis of saidstamping wheel, and a selected character carrier can be pushed radiallyoutward through a radial outlet opening in the stamping wheel. Thedisadvantage of this type of device, however, consists in the fact thatthe character carriers can only be transported to the outlet opening inthe order in which they are arranged in the stamping character storage.Additionally, devices of this type suffer from the disadvantage thatexchanging of a larger number of character carriers of a charactercarrier set also requires exchanging of the entire exchangeablecartridge containing the character set.

Therefore, the object of the present invention consists in providing adevice for the marking of parts moving in the direction of motion of aconveying device that allows, on the one hand, fast automatic exchangingof substantially entire sets of character carriers where each of thecharacter carriers, however, is exchanged separately and this exchangeoperation takes place quickly and substantially automatically with aview to production speed and, on the other hand, particularly fastmarking of parts in cases where the difference between two consecutivestamping operations is limited to one different character in thecharacter set used, this one character to be exchanged substantiallybeing freely selectable.

This object is attained by a device of the type indicated above byproviding at least one character carrier magazine for charactercarriers, ensuring that the character carrier magazine and the stampingwheel can be moved into positions relative to each other where charactercarriers of the stamping wheel can be directly transferred intoreceptacles of the character carrier magazine and character carriers ofthe character carrier magazine can be directly transferred intoreceptacles of the stamping wheel, and by providing a pivotally mountedmagazine revolver being coaxial with the stamping wheel and containingcharacter carrier pins radially movable therein, at least one outletchannel in the stamping wheel radially extending to the circumference ofsaid stamping wheel and a linear drive non-pivotally mounted on thestamping wheel enabling radial shifting of a character carrier pinlocated in the angular position of the outlet channel from an internalinoperative position to an external impacting position.

The invention disclosed hereunder allows fast marking of parts,especially sections, with different characters, the invention standingout for particularly great flexibility as far as the type of marking isconcerned.

In this respect, it is advantageous to connect with the linear drive athrust piece that can, with a nose, engage in a groove of the charactercarrier pin. With the help of this thrust piece, the character carrierpin can be moved into its impacting position or drawn from its impactingposition back into its internal inoperative position, respectively.

Additionally, it is advantageous to provide springs keeping thecharacter carrier pins in their respective inoperative positions in themagazine revolver. Thus, radial dislocation of the character carrierpins during rotation of the magazine revolver caused by the centrifugalforce and/or gravity occurring during rotation is prevented so thatunhindered engaging of the thrust piece with its nose in a groove of therespective character carrier pin being transported into the outletchannel is ensured.

In a practically tested and reliable embodiment, the linear drive is ahydraulic drive.

It is also recommendable to position the outlet channel within the areaof the character carriers inserted at the circumference of the stampingwheel in order to allow modification of the character set by exchanginga character carrier pin located in its impacting position in the outletchannel.

It is, furthermore, of advantage to provide clamping pieces to clamp thecharacter carriers into the receptacles of the stamping wheel and toprovide springs to clamp the clamping pieces into the recesses of thecharacter carriers. Thus the character carriers in the receptacles ofthe stamping wheel are protected against dislocation during the stampingoperation and positioning of the stamping wheel in the exchangeposition.

It is recommendable to provide releasing pins acting on the clampingpieces located in bores substantially parallel to the axis at thecircumference of the stamping wheel to release the clamped charactercarriers, thus creating the preconditions for moving the charactercarriers into the character carrier magazine.

If is, furthermore, of advantage to provide drivable pins to pushcharacter carriers out of the stamping wheel into a receptacle of thecharacter carrier magazine as well as drivable pins to move charactercarriers out of the character carrier magazine into the stamping wheel.Said pins allow substitution of character carriers from the charactercarrier magazine for character carriers from the stamping wheel and viceversa.

Additionally, it is recommendable to design the character carriermagazine, one character carrier magazine representing the absolutelyrequired minimum, in such a way that it is wheel-shaped and can berotated around its own axis and to position character carriers that canbe radially shifted at the circumference of said character carriermagazine. Thus it is possible to position the character carrier to beexchanged of the character carrier magazine, by rotating the charactercarrier magazine, in the immediate vicinity of the receiving positionfor the character carrier in the stamping wheel in such a way that thecharacter carrier can then be transferred into the receptacle of thestamping wheel.

Another advantageous feature, finally, consists in a distance measuringdevice for the moving parts being provided to ensure that the positionof the stamping unit carrying the stamping wheel is adequately adjustedas said parts move along. With the help of said distance measuringdevice, the horizontal deviation from a theoretical position of theparts to be marked moving on a conveying device is determined, and thestamping wheel can be permanently kept above the parts to be marked withthe help of a position adjusting mechanism.

In the following, the invention is described, in the form of onepossible embodiment, on the basis of the drawings.

FIG. 1 shows a section through part of a device according to the presentinvention with a revolving magazine connected to the stamping wheel.

FIG. 2 shows a section through a character carrier holder with charactercarriers inserted therein and an outlet channel.

FIG. 3 shows a section trough part of a device according to the presentinvention with a stamping wheel mounted in a stamping unit and awheel-shaped character carrier magazine connected thereto.

FIG. 1 shows a stamping wheel 2, in this embodiment eccentricallydesigned, with character carriers 3 for the marking of parts 1,especially sections such as rails, moving on a conveying device,inserted at the circumference of a partial segment. These charactercarriers 3 are, as illustrated in FIG. 2, inserted in a charactercarrier holder 4. The stamping wheel 2 can be accelerated with the helpof a drive 7, and its circumferential speed can be synchronized takingthe speed of the moving parts 1 into account. For this purpose, thestamping wheel 2 is driven via a spur gear 8 and 9 and the rollingbearings 10 and 11 together with the pertaining additional elementsknown to the expert. Additionally, a distance measuring device 6 isshown that allows continuous horizontal adjustment, with the help of adrive provided for this purpose, of the position of the stamping wheel 2above the parts 1 to be marked.

The character carrier holder 4, illustrated in detail in FIG. 2,contains several character carriers 3 arranged in a row one behind theother at identical or different intervals, thus yielding a curvedarrangement of character carriers 3. These character carriers 3, whichcan be different or partly or entirely identical character carriers, areclamped with the help of clamping pieces 12 that are located inrectangular slip-in guides in the character carrier holder 4 and engagein recesses in the character carriers 1, thus protecting them againstradial dislocation in relation to the stamping wheel 2. Springs 13 andthrust pins 26 are used to press the clamping pieces 12 radially in thedirection of the axis of symmetry S of the stamping unit 2 in order toclamp the character carriers 3. This axis of symmetry S as well as thestamping unit 27 are shown in FIG. 3.

Due to the eccentricity of the stamping wheel 2, contact occurs—afterpartial rotation of the stamping wheel 2 by the drive 7 arrangedparallel to the center line of the stamping wheel 2 and withsynchronization duly taking the speed of the parts 1 passing under thestamping wheel as well as speed changes, if any, into account—betweenthe stamping roller 2 and the part passing below the stamping wheelimmediately before the partial segment at the circumference of thestamping roller 2 where the character carriers 3 are inserted in thecharacter carrier holder 4.

The force thereby exerted by the part 1 to be marked against thestamping wheel 2 and, thus, against the entire stamping unit 27 in whichthe stamping wheel 2 is pivotally mounted, which causes lifting of thestamping unit 27 above its suspension and guiding system, iscounteracted by an automatically pre-adjusted force required for therespective parts to be marked, thus ensuring that stamping is performedwith constant and adequate pressure. The stamping unit 27 is shown inFIG. 3.

After this marking operation, the stamping roller 2, on grounds of itseccentricity, moves away from the part to be marked as it continues torotate. The marking operation can now be terminated, repeated with thesame character set or the character set can, in whole or in part, beexchanged for a subsequent stamping operation. Additionally, it ispossible to imprint, for example, a series of consecutive markings whereonly one sign of the character set used changes from one markingoperation to the next.

As also shown by FIG. 1, a revolving magazine 15 containing one orseveral character carrier pins 5 movably arranged in radial slip-inguides 16 along its circumference is, via a rolling bearing 14, mountedin such a way that it is coaxial with the stamping wheel 2. In order toexchange a single character carrier of a character carrier set betweentwo consecutive marking operations directly and quickly following eachother, one character carrier pin 5, located in its impacting position inan outlet channel 20 of the stamping wheel 2 in the area of thecharacter carrier holder 4 and being flush with the other charactercarriers 3, as shown in FIG. 2, is, with the help of a thrust piece 17controlled by a hydraulic linear drive 18 working parallel to thestamping axis Z, moved into its radial internal inoperative position.The character carrier 5 is thus located outside the outlet channel 20 inthe character carrier holder 4 and can thus be freely rotated with therevolving magazine 15 within the eccentric stamping wheel 2.

With the help of the drive 19, the coaxially arranged revolving magazine15 can then, within the stamping wheel 2 and irrespective of theposition of the stamping wheel 2, be rotated in any desirable directionaround its bearing axis until another character carrier pin 5 insertedin the revolving magazine 15 enters the area of the outlet channel 20.

With the help of the linear drive 18 and via the thrust piece 17,another pre-selected character carrier pin 5 is pushed through theoutlet opening 20 into the external impacting position at thecircumference of the stamping wheel 2 until it is flush with the othercharacter carriers 3. In this position, the character carrier pin 5 is,with a constant force exceeding the force exerted by the parts to bemarked during the marking operation, held by the thrust piece, the thusrequired force being produced by the linear drive 18.

The further character carrier pins 5 arranged in the revolving magazine15 that are not located in the area of the outlet channel, are, viapressure springs 21 counteracting radial dislocation as a consequence ofcentrifugal force and/or gravity, kept in their internal inoperativepositions. Thus unhindered engaging of the thrust piece 17, with itsnose, in a groove of the character carrier pin 5 moving into the outletchannel is enabled. The character carrier pins 5 can thus, in theirslip-in guides, only be moved in combination with the thrust piece 17,inverted positioning of noses and grooves, of course, also beingpossible, i.e. the noses can be formed to the character carrier pins 5and the grooves to the thrust piece 17. The clamping pieces 22 mountedon the character carrier pins 5 permanently secure these against axialrotation in relation to the stamping axis Z

This exchange operation takes less than one second and takes placebetween two stamping operations, can be repeated several times andensures that several consecutive stamping operations printing adifferent or identical stamp image can be performed within a very shorttime.

The drive 19, fixed on the housing 23 that is pivotally mounted via therolling bearings 10 and 11 and connected with the stamping roller, issupplied with energy via the slip ring 24, while a rotatable fluidconnection 25 is used to supply energy to the drive 18 that isnon-pivotally mounted on the stamping roller 2.

Closer inspection of FIG. 3 reveals another possibility of exchangingcharacter carriers that consists in moving the stamping wheel 2,pivotally mounted within the stamping unit 27, into a radial angularposition pre-determined for a character carrier exchange operation, sothat a character carrier 3 can be transferred from the stamping wheel 2into an empty receptacle 28 of a—in the case of the present embodimentwheel-shaped—character carrier magazine 29 and a character carrier fromsaid character carrier magazine 29 can be transferred into an emptyreceptacle of the stamping wheel 2.

In this precisely defined position, several character carriers 3radially arranged at the circumference of the stamping wheel 2 aresimultaneously and automatically exchanged as described below. Thereceptacles for the character carriers 3 are, in the present embodiment,located in the character carrier holder 4 that is radially arranged in apartial segment at the circumference of the stamping wheel. Thischaracter carrier holder 4, shown in detail in FIG. 2, contains severalcharacter carriers 3 arranged in a row one behind the other at identicalor different intervals, thus resulting in a curved arrangement of thecharacter carriers 3. These character carriers 3, which can be differentor partly or entirely identical character carriers, are, during thestamping operation and during positioning of the stamping wheel 2 in theexchange position, clamped radially to the axis of symmetry S of thestamping unit 27 in which the stamping wheel 2 is pivotally mounted, byclamping pieces 12 that are located in rectangular slip-in guides in thecharacter carrier holder 4 and engage in recesses of the charactercarriers 3. Springs 13 and thrust pins 26 are used to push the clampingpieces 12 radially in the direction of the axis of symmetry S of thestamping unit 27 in order to clamp the character carriers 3.

After positioning the stamping wheel 2 in the character exchangeposition, the clamping pieces 12 must, at the beginning of the exchangeoperation, be lifted, within the prismatic slip-in guides of thecharacter carrier holder 4 and radially to the axis of symmetry S of thestamping unit 27, in the direction of the circumferential edge of thestamping wheel 2 until the character carriers 3 to be exchanged are nolonger clamped in place and unhindered moving of the character carriers3 parallel to the axis of symmetry S of the stamping unit 27 in therecesses provided for this purpose in the character carrier holder 4 isenabled.

For this purpose, releasing pins 30 with chamfered ends are insertedinto the character carrier holder 4 through bores 31 located at thecircumference of the stamping wheel 2 and extending in a directionparallel to the axis of symmetry S of the stamping unit 27, thus causingthe clamping pieces 12 to be lifted by the releasing pins 30 in thedirection of the circumferential edge of the stamping wheel 2 andenabling moving of the character carriers 3 within the character carrierholder 4 in a direction parallel to the axis of symmetry S of thestamping unit 27. The releasing pins 30 are arranged on a slide 33mounted on linear guides 32 in a curve corresponding to the curvedarrangement of the clamping pieces 12 in the character carrier holder 4.The insertion of the releasing pins 30 mounted on the slide 33 iscontrolled by pneumatic cylinders 34, the number of cylinders 34 useddepending on the number of character carriers 3 to be exchanged. Thepneumatic cylinders 34 stay in their most recent position until thecharacter carriers 3 have been exchanged.

The character carriers 3, being unsecured after lifting of the clampingpieces 12, are secured against dropping out of the character carrierholder 4 by means of pins 35 with chamfered ends. For this purpose, pins35, arranged on a slide 36 in a curve corresponding to the arrangementof the character carriers 3 in the character carrier holder 4 that are,parallel to the linear guide 37 holding the slide 36, offset in such away that insertion of the pins 35 into the interior of the charactercarrier magazines 29 is enabled, are pressed against the charactercarriers 3 in a direction parallel to the axis of symmetry S of thestamping unit 27 by means of the pneumatic cylinders 38.

Pneumatic cylinders 39, the number of which also depends on the numberof character carriers to be exchanged, are used to insert pins 40 withchamfered tips into further bores arranged in a curve at thecircumference of the stamping wheel 2 and extending parallel to the axisof symmetry S until they thrust against the pins 35 securing thecharacter carriers 3 against dropping out of the character carrierholder 4. Further insertion of the pins 40 causes the character carriers3, now protected against rotation as a consequence of being clamped bythe pins 35 and 40, to be moved in the direction of the charactercarrier magazines 29 along a path parallel to the axis of symmetry S ofthe stamping unit 27.

Said wheel-shaped character carrier magazines 29 are provided, at theircircumference, with several rectangular receptacles 41 extendingradially to their central points and containing different charactercarriers. The character carrier magazines 29 are located in positionswhere one empty receptacle is located directly opposite one charactercarrier 3 to be exchanged located in the stamping wheel 2. Generally,these positions of the character carrier magazines 29 are those wherethe magazines 29 remained after the most recent exchange operation. Thecharacter carriers 3 are now, as described above, moved until they restagainst a radial ring-shaped stop 41 in the respective character carriermagazine 29, thus preventing further inward movement of the charactercarriers. The pneumatic cylinders 39 are then moved back into theirinitial positions corresponding to their top end positions, thusenabling rotary movement of the wheel-shaped character carrier magazines29.

Gear wheels 43 driven via toothed belts 42 are used to rotate andposition each character carrier magazine 29 in such a way that apre-selected character carrier required for the respective next markingoperation is facing in the direction of the outlet position, i.e. ispositioned parallel to the axis of symmetry S of the stamping unit 27 inthe direction of the character carrier holder 4. During the rotationalmovement performed by the character carrier magazines 29, the charactercarriers 3 are by means of external ring-shaped guides 44 prevented fromdropping out. Exact positioning of the character carriers throughrotational movement of the character carrier magazine 29 is additionallymonitored by means of the monitoring switch 45.

After moving of the character carrier magazine 29 into the positionrequired for the exchange operation, the pins 40, controlled by thepneumatic cylinder, are moved until they press the character carrier tobe moved out of the magazine 29 into a receptacle of the stamping wheel2 against the ring-shaped stop 41. Then the character carriers are, bythe pins 35 moving into the receptacles 41 and the pins 40, clamped inplace, thus protecting them against rotation. Further insertion finallycauses the character carriers to be inserted into the receptaclesprovided for this purpose in the character carrier holder 4 of thestamping wheel 2. The pneumatic cylinder 34 is moved back into itsinitial position, which at the same time causes the releasing pins 30 tobe moved out of the character carrier holder 4 along a path parallel tothe axis of symmetry S. This causes the clamping pieces 12, initiallypushed radially upward in the direction of the circumferential edge ofthe stamping wheel 2 by the releasing pins 30, to be pushed in thedirection of the axis of symmetry S by the springs 13, thus locking thenewly inserted character carrier in place.

The character carrier exchange mechanism described immediately above isparticularly suitable for the exchanging of parts of a character set orentire character sets, respectively. This mechanism can, of course, alsobe used to exchange only individual character carriers of a set. In thecase of said exchange operation to be performed during two consecutivestamping operations following each other at a short interval, it is morepreferable to use the individual character carrier exchange mechanismdescribed further above.

The particular advantage offered by the device described herein consistsmainly in its flexibility as far as the marking of parts moving on aconveying device, e.g. the marking of sections with different charactersets, is concerned as the device can be operated without an exchangemechanism or, optionally, with one or both of the two mechanismsdescribed herein.

A further advantage offered by the device described herein consists inthe fact that the eccentric stamping wheel pivotally mounted in thestamping unit can, by means of the distance measuring device for theparts to be marked, permanently be kept above the parts to be marked bya suitable type of drive, even in cases where said parts deviate fromtheir theoretical marking position. A detailed description hereof iscontained in a parallel application under the Hungarian applicationnumber P 97 02 363.

What is claimed is:
 1. Device for the marking of parts (1) moving in thedirection of motion of a conveying device such as a roller table, havingat least one character carrier (3) carrying one character, saidcharacter carrier being exchangeably inserted at the circumference of astamping wheel (2), wherein at least one character carrier magazine (29)for character carriers (3) is provided and the character carriermagazine (29) and the stamping wheel (2) can be moved into positionsrelative to each other where character carriers of the stamping wheel(2) can be directly transferred into receptacles (28) of the charactercarrier magazine- (29) and character carriers of the character carriermagazine (29) can be directly transferred into receptacles of thestamping wheel (2), and wherein a magazine revolver (15) containingcharacter carrier pins (5) radially movable therein is pivotally mountedin such a way that it is coaxial with the stamping wheel (2), at leastone outlet channel (20) radially extending to the circumference of thestamping wheel is provided in the stamping wheel and a linear drive (18)non-pivotally mounted on the stamping wheel (2) is provided for radialshifting of a character carrier pin (5) located in the angular positionof the outlet channel from an internal inoperative position to anexternal impacting position.
 2. Device according to claim 1, wherein athrust piece (17) that can engage with a nose in a groove of thecharacter carrier pin (5) is connected with the linear drive (18). 3.Device according to claim 1, wherein the character carrier pins (5) areheld in their inoperative positions in the magazine revolver (15) bysprings (21).
 4. Device according to claim 2, wherein the linear drive(18) is a hydraulic drive.
 5. Device according to claim 1, wherein theoutlet channel (20) is located in the area of the character carriers (3)inserted at the circumference of the stamping wheel (2).
 6. Deviceaccording to claim 1, wherein the character carriers (3) can be clampedin the receptacles of the stamping wheel (2) by clamping pieces (12). 7.Device according to claim 6, wherein the clamping pieces (12) can beclamped in a recess of the character carrier (3) by means of springs(13).
 8. Device according to claim 1, wherein the clamped charactercarriers (3) can be released by means of releasing pins (30) acting onthe clamping pieces (12) and located in bores (31) essentially arrangedparallel to the axis at the circumference of the stamping wheel (2). 9.Device according to claim 1, wherein drivable pins (40) for movingcharacter carriers (3) out of the stamping wheel (2) into a receptacle(28) of the character carrier magazine (29) as well as drivable pins(35) for moving character carriers out of the character carrier magazine(29) into the stamping wheel (2) are provided.
 10. Device according toclaim 1, wherein the character carrier magazine (29), one charactercarrier magazine representing the absolute minimum required, iswheel-shaped and can be rotated around its own axis.
 11. Deviceaccording to claim 10, wherein character carriers that can be moved in aradial direction are arranged at the circumference of the wheel-shapedcharacter carrier magazine (29), one character carrier magazinerepresenting the absolute minimum required.
 12. Device according toclaim 1, wherein a distance measuring device (6) for the moving parts isprovided in order to allow adjustment of the position of the stampingunit (27) carrying the stamping wheel (2).